477. Trends in the Incidence of Community-Associated and Healthcare-Associated Clostridium difficile Infections in Quebec over a 7-Year Period (2008-2015)
Session: Poster Abstract Session: Healthcare Epidemiology: Updates in C. difficile
Thursday, October 4, 2018
Room: S Poster Hall
  • Final-Poster Idweek 20180920 (1).pdf (443.3 kB)
  • Background:

    Clostridium difficile infections (CDI) affect hospitalized patients but also individuals in the community. The epidemiology of healthcare-associated (HA) CDI has received much scrutiny, but little is known regarding trends in the incidence rate of community-associated (CA) cases. We describe and compare long-term trends in the provincial incidence rate of CA-CDI and HA-CDI.


    Hospitalized patients with CA-CDI and HA-CDI were identified prospectively between April 2008 and April 2015 through the Quebec CDI surveillance program (QCISP), a network of 95 acute-care institutions using standardized case definitions. Hospitalized CDI cases are classified as CA if they occur within 3 days of admission or > 4 weeks after any inpatient or outpatient care. CDI cases are defined as HA-CDI if they occurred >3 days after admission and up to 4 weeks following discharge. Trends in the incidence of HA-CDI and CA-CDI were compared using time series with segmented regression and Poisson law.


    Between 2008 and 2015, 28,850 CDI were detected in hospitalized patients. Of these 4,481 (15.5%) were CA and 24,369 (84.5%) HA-CDI. The annual CA-CDI incidence rate increased by 35.2% from 0.51 to 0.68 per 100.000 population (Incidence rate ratio [IRR] per 4-week period, 1.005; 95% confidence interval [CI], 1.004 to 1.006; p<0.0001) whereas the incidence of HA-CDI remained stable from 6.6 to 7.0 per 10.000 patient-days (IRR per 4-week period, 1.000; 95% CI, 0.999 to 1.000; p=0.23). There was a significant difference between the trends in incidence of CA-CDI and HA-CDI (IRR, 1.005; 95% CI, 1.004 to 1.006; p < 0.0001). Further analysis showed an inflection point in the incidence of HA-CDI in April 2011 with a reduction in slope (change in trend, IRR, 0.997; 95% CI, 0.995 to 0.999; p=0.007). No concomitant change was seen in the trend of CA-CDI (change in trend, IRR, 0.997; 95% CI, 0.992 to 1.002; p=0.2) despite a slight immediate change in level at inflection point (IRR, 1.131; 95% CI, 1.000 to 1.278; p=0.05).


    Between 2008 and 2015, the provincial incidence of hospitalized CA-CDI has significantly increased while the incidence rate of HA-CDI has remained relatively stable. Further studies are required to investigate the factors underlying this increase.

    Veronica Zanichelli, MD1, Christophe Garenc, PhD2,3, Jasmin Villeneuve, MD2, Danielle Moisan, MD4, Charles Frenette, MD, FSHEA5,6, Yves Longtin, MD1,6,7 and Québec Clostridium difficile Infection Surveillance Program (QCISP), (1)Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, QC, Canada, (2)Institut National de Santé Publique du Québec, Québec City, QC, Canada, (3)Centre de Recherche en Infectiologie de l'Université Laval, Québec City, QC, Canada, (4)Department of Medical Microbiology, CSSS Rivière-du-Loup, Rivière-du-Loup, QC, Canada, (5)McGill University Health Center, Montréal, QC, Canada, (6)Faculty of Medicine, McGill University, Montréal, QC, Canada, (7)Jewish General Hospital Sir Mortimer B. Davis, Montréal, QC, Canada


    V. Zanichelli, None

    C. Garenc, None

    J. Villeneuve, None

    D. Moisan, None

    C. Frenette, None

    Y. Longtin, Merck: Grant Investigator , Research grant . Becton Dickinson: Grant Investigator , Grant recipient .

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